Field of the Invention
The invention relates to a pixel array substrate and a display, and more particularly to a pixel array substrate applicable to an organic light-emitting diode (OLED) display and an OLED display.
Description of Related Art
At present, displays are categorized into plasma displays, liquid crystal displays (LCD), inorganic electroluminescent displays, organic light-emitting diode (OLED) displays, field emission displays (FED), electro-chromic displays, and so forth. Compared with other types of displays, the OLED display has potential to become the mainstream in the next generation, for it has the advantages of self-luminescence, no viewing angle dependence, low power consumption, wide range of working temperature, fast response speed, full-color display, etc.
A conventional OLED display includes a plurality of pixel units distributed onto a substrate. Each of the pixel units includes a switch transistor, a driver transistor electrically coupled to the switch transistor, and a pixel electrode electrically coupled to the driver transistor. A constant voltage line transmits a constant voltage to an input electrode of the driver transistor of each pixel unit, such that the driver transistor is allowed to work in an amplification region. When the driver transistor stably works in the amplification region, the driver transistor is able to provide constant current to an OLED layer, and thereby each pixel unit is able to display images with proper brightness.
However, the distances from the pixel units distributed onto the substrate to a constant voltage source are inconsistent, thus leading to the difference in resistances between the input electrodes of the driver transistors and the constant voltage source. In this case, the constant voltage respectively transmitted to the input electrodes of the driver transistors may vary, and thereby the OLED display is not able to display images with favorable display quality.
From another perspective, in the conventional OLED display, a common electrode layer and a control electrode of the driver transistor may together constitute a pixel storage capacitor. Due to the excessively long distance between the common electrode layer and the control electrode of the driver transistor, the pixel storage capacitance is low, which poses a negative impact on the display effects of the OLED display.